(a) Field of the Invention
This invention relates to portable electronic devices with a display part and particularly relates to those in which a display part is supported changeably between a vertical position and a horizontal position.
(b) Description of the Related Art
An increasing number of portable electronic devices, especially mobile phones, have been having a TV receiving function in Japan owing in part to start of Integrated Service Digital Broadcasting-Terrestrial (ISDB-T) for portable electronic devices in this country.
The terrestrial digital television broadcasting, unlike conventional analog television broadcasting, can provide so-called bidirectional service including viewers' participation in quiz shows via TV sets and use of TV shopping or bank remittance via TV sets. When the terrestrial digital television broadcasting can be viewed on a mobile phone, this further increases the need for the user to operate keys on the operating part while viewing images on the display part. TV images are normally landscape. Therefore, in order that the user views TV images as large as possible on a small liquid crystal display part, the liquid crystal display part needs to be placed in a horizontal position.
To cope with this, for example, Published Japanese Patent Application No. 2004-215180 discloses a portable wireless electronic device whose body includes a first housing with a plurality of operation keys, a second housing with a display having a rectangular screen of predetermined aspect ratio and a connecting part connecting the first and second housings to each other and including a pivot mechanism for turning the second housing with respect to the first housing along a plane parallel with the screen. The second housing is configured to display images, during wireless communication, in a position in which the screen is vertically oriented and display images, during TV watching, in a position in which the screen is horizontally oriented.
Alternatively, Published Japanese Patent Application No. 2006-211576 discloses a portable electronic device in which a first housing having a display part is connected to a second housing having an operating part by a hinge to allow both the housings to be freely opened and closed in their folded form and the display part is guidedly supported by a cam mechanism so that one of its lower corners can move along the hinge upon position change between vertical and horizontal positions. Thus, the display part can be increased in size in spite of reduction of the entire electronic device size and can be easily changed between vertical and horizontal positions, and the user can easily operate the operating part while viewing the display part even in the horizontal position.
However, in the portable electronic device disclosed in Published Japanese Patent Application No. 2004-215180, the operation from during non-use to during TV watching is a cumbersome operation of first opening the second housing, turning it from vertical to horizontal position and then sliding it.
On the other hand, in the portable electronic device disclosed in Published Japanese Patent Application No. 2006-211576, the operation from during non-use to during TV watching is a simple operation of opening the first housing and turning it from vertical to horizontal position. However, since the portable electronic device has a structure in which the three housings composed of the display part, the first housing supporting the display part and the second housing are connected, there is a definite limit to reducing the entire thickness of the electronic device.